Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261397AbVC0CE5 (ORCPT ); Sat, 26 Mar 2005 21:04:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261398AbVC0CE5 (ORCPT ); Sat, 26 Mar 2005 21:04:57 -0500 Received: from inti.inf.utfsm.cl ([200.1.21.155]:30610 "EHLO inti.inf.utfsm.cl") by vger.kernel.org with ESMTP id S261397AbVC0CEy (ORCPT ); Sat, 26 Mar 2005 21:04:54 -0500 Message-Id: <200503270200.j2R20eM4006733@laptop11.inf.utfsm.cl> To: Marcin Dalecki cc: linux-os@analogic.com, ext2-devel@lists.sourceforge.net, Linux kernel , Arjan van de Ven , Jesper Juhl Subject: Re: [PATCH] no need to check for NULL before calling kfree() -fs/ext2/ In-Reply-To: Message from Marcin Dalecki of "Sun, 27 Mar 2005 00:34:12 +0100." <7d96f2772f942f802890c50801c4f5f8@dalecki.de> X-Mailer: MH-E 7.4.2; nmh 1.1; XEmacs 21.4 (patch 17) Date: Sat, 26 Mar 2005 22:00:40 -0400 From: Horst von Brand Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1411 Lines: 38 Marcin Dalecki said: > On 2005-03-27, at 00:21, linux-os wrote: > > Always, always, a call will be more expensive than a branch > > on condition. Wrong. > > It's impossible to be otherwise. Many, many counterexamples say otherwise... > > A call requires > > that the return address be written to memory (the stack), Not necesarily right now, it can be done at leisure later on while doing other stuff. > > using register indirection (the stack-pointer). So what? The stack pointer is surely special. Modern programming languages (and programming styles) encourage many calls, so this is very heavily optimized. > Needless to say that there are enough architectures out there, which > don't even have something like an explicit call as separate assembler > instruction... The mechanism exists somehow. -- Dr. Horst H. von Brand User #22616 counter.li.org Departamento de Informatica Fono: +56 32 654431 Universidad Tecnica Federico Santa Maria +56 32 654239 Casilla 110-V, Valparaiso, Chile Fax: +56 32 797513 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/